2008 Cadillac DTS Owner's Manual - Page 184

PASS (Passenger's Climate Control): Press this button to turn the passenger's climate control systems on or off. When the passenger's climate control system is on, the passenger's temperature setting is displayed. The temperature selected by the front passenger also controls the rear system air temperature unless the rear seat passengers select their own comfort setting. If the PASS button is pressed to turn the passenger temperature setting off, the driver's temperature knob will control the temperature for the entire vehicle. AUX: If your vehicle has a rear climate control system, press this button to turn the rear climate control fan on for automatic operation. After the AUX button is pressed, the indicator light comes on. Press the button again to turn the auxiliary fan off. See Rear Climate Control System on page 3-47. Sensors #(Air Conditioning): Press the center of the left control knob to override the automatic system and turn the air conditioning system on or off. When in AUTO, the air conditioning compressor comes on automatically, as necessary. The air conditioning system removes moisture from the air, so a small amount of water may drip underneath the vehicle while idling or after turning off the engine. This is normal. The solar sensor, located in the defrost grille, middle of the instrument panel, monitors the solar radiation. Do not cover the solar sensor or the system will not work properly. 3-44